1. Unplug those USB flash drives during normal use. Can slow a PC.
2. Norton Internet Security. There are numerous complaints about this title and issues.
Since this is W10, I'd eject this and go stock. Windows Defender is fine for those that just surf and keep away from bad sites, don't torrent, etc.
3. Check this item out. Disable update sharing.
https://www.howtogeek.com/224981/how-to-stop-windows-10-from-uploading-updates-to-other-pcs-over-the-internet/
To me this machine looks very clean. HDD is in good health, memory is proper with dual channel working. If this was mine I'd try the 3 things above PLUS test with another DNS. Try 8.8.8.8
I have a Toshiba Satellite C55-C5241 15.6 Inch Laptop (Intel Core i5, 8 GB, 1TB HDD with Windows 10.
The browsers on my computer are extremely sluggish and say "not responding" This is true with Chrome, FireFox and Edge. It happened as well with the app for OneDrive sign in. I got rid of a bunch of add ons and extensions, but that didn't seem to help.
About 2 months ago I thought my laptop was dying but before buying a new one, I decided to wipe out everything and reinstall windows. It worked like a charm until the last few days.
It does seem that things run smoother once the computer is warmed up, but that has taken 2-3 hours today.
I don't know if my problem is the computer or a router issue. How do you know if it is a router problem?

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